uid=HFR,o=lter,dc=ecoinformatics,dc=org all public read doi:10.6073/pasta/336327978cb4ddfdf253061b6fa92d7b Catherine Langtimm Rebecca Field John O'Keefe Researcher 2023 English

Recently several authors have documented fluctuations in the abundance of white-footed mice (Peromyscus leucopus noveboracensis) with fluctuations in acorn production (Elkinton et al. 1996, Ostfeld et al. 1996, Wolff 1996, Jones et al. 1998). Acorns are the major food source of white-footed mice during winter and are extensively cached. They are also food for many other species as well; over 100 species of birds and mammals feed on acorns (Van Dersal 1940). A large mast crop in fall usually correlates with a large mouse population the following summer, whereas a poor crop correlates with low population numbers. One experimental study supplementing acorns on forest plots demonstrated a concomitant increase in white-footed mice populations (Jones et al. 1998). It has been hypothesized that a large mast crop increases overwinter survival and may allow continued reproduction during the winter months, which results in a larger population the following year. We have four objectives in monitoring acorn abundance at Harvard Forest: 1) test for correlation of estimates of acorn production with estimates of overwinter survival probabilities and abundance of white-footed mice using mark-recapture statistical models (HF054), 2) document annual variation in acorn abundance and quality, which compliments a program at Harvard Forest documenting changes in woody plant phenology with climatic variation (HF003), 3) test hypotheses concerning the correlation of acorn production with environmental factors such as temperature, rainfall, and weevil infestation, and 4) provide data for inter-site comparisons, such as to test for synchrony in production at various scales across the landscape. We estimate acorn production with timed visual surveys following methods adapted from Koenig et al. (1994). Individual tagged trees on two small mammal trapping plots are surveyed each year by two observers. Detailed methods are described in the metadata.

abundance mammals oak population dynamics production LTER controlled vocabulary populations LTER core area Harvard Forest HFR LTER USA HFR default

This dataset is released to the public under Creative Commons CC0 1.0 (No Rights Reserved). Please keep the dataset creators informed of any plans to use the dataset. Consultation with the original investigators is strongly encouraged. Publications and data products that make use of the dataset should include proper acknowledgement.

Creative Commons Zero v1.0 Universal https://spdx.org/licenses/CC0-1.0.html CC0-1.0 https://harvardforest.fas.harvard.edu/exist/apps/datasets/showData.html?id=hf030 Harvard Forest. Coordinates based on WGS84 datum. -72.23 -72.16 +42.55 +42.44 417 208 meter 1997 1999 genus Peromyscus species leucopus white-footed mouse complete Information Manager Harvard Forest

324 North Main Street Petersham MA 01366 USA

(978) 724-3302 hf-im@lists.fas.harvard.edu Harvard Forest

324 North Main Street Petersham MA 01366 USA

(978) 724-3302 (978) 724-3595 https://harvardforest.fas.harvard.edu

Visual surveys of acorns in the crown of individually tagged oak trees are made each year in late summer. Methods were modified from Koenig, W. A. et al. 1994. Estimating acorn crops using visual surveys. Canadian Journal of Forestry Research 24:2105-2112. The nearest dominant or co-dominant oak tree at each station on the small mammal trapping grid is surveyed by two observers scanning the crown with binoculars. Each observer takes turns systematically scans the crown, counting out loud the number of acorns seen. A recorder with a stop watch records the total count at 15, 20, 25, and 30 seconds. After the count each observer classifies the crop into one of five general conditions and comments on the number of acorns on the ground under the tree.

Harvard Forest

324 North Main Street Petersham MA 01366 USA

(978) 724-3302 (978) 724-3595 https://harvardforest.fas.harvard.edu https://ror.org/059cpzx98 pointOfContact The Harvard Forest Long-Term Ecological Research (LTER) program examines ecological dynamics in the New England region resulting from natural disturbances, environmental change, and human impacts. National Science Foundation LTER grants: DEB-8811764, DEB-9411975, DEB-0080592, DEB-0620443, DEB-1237491, DEB-1832210. hf030-01-acorn.csv acorn data hf030-01-acorn.csv 18945 2505f1e15b521dc54f3f6978c389538f 1 \r\n column , https://harvardforest.fas.harvard.edu/data/p03/hf030/hf030-01-acorn.csv date date YYYY-MM-DD stand stand PH Prospect Hill TS Tom Swamp station small mammal trap station small mammal trap station tree tree number tree number species species RO red oak WO white oak dbh diameter at breast height centimeter 0.1 real NA missing value acorns acorns on ground NONE no acorns on ground FEW few acorns on ground SOME some acorns on ground MANY many acorns on ground observer observer (1-3) observer sec15 #acorns at 15 sec number 1 whole NA missing value sec20 #acorns at 20 sec number 1 whole NA missing value sec25 #acorns at 25 sec number 1 whole NA missing value sec30 #acorns at 30 sec number 1 whole NA missing value class characterization of acorn crop 0 no acorns observed 1 poor crop; one or a few acorns observed 2 fair crop; singles and doubles occur scattered through crown 3 good crop; cluster of acorns throughout crown 4 excellent crop; acorns throughout crown 391 community short-term measurement https://harvardforest.fas.harvard.edu/exist/apps/datasets/showData.html?id=hf003 https://harvardforest.fas.harvard.edu/exist/apps/datasets/showData.html?id=hf054